假丝酵母属的聚类分析和代谢活性的研究

METABOLISM ACTIVITY AND CLUSTER ANALYSIS OF STRAINS OF THE GENUS CANDIDA

本文对35株假丝酵母测定了84项性状,用不同的聚类方法进行了聚类,结果以Ssm系数的UPGMA方式处理较合适。根据UPGMA聚类结果,这些菌株主要分成两大类群。对代谢活性(生理生化性状的阳性百分率,MA%)分析的结果发现,第一类群的代谢活性在40%至73%之间,而第二类群在9%至33%之间,类群间代谢活性有明显差异。实验结果还表明,某些传统鉴定方法中的鉴定指标(如硝酸盐同化等)不能代表类群的特征,而另外一些指标(如MA%,海藻糖、松三糖和麦芽糖的同化等)具有类群的特征性。虫生假丝酵母(C.insectorum)和穿凿假丝酵母(C.terebra)的相似性系数高达90%,这两个种应该合并为一种。

Eighty four characteristics of 35 strains belonging to the genus Candida have been measured.Diffierent cluster methods were used,and UPGMA cluster method based on Ssm similarity coefficient has been found the best,according the above method,these strains are divided into two groups.The analysis of metabolism activity (positive rate of bioche- mical and physiological characteristics,MA%) indicates that MA% has closely relationship with cluster groups,MA% of the first group is from 40% to 73%,and the second group is from 9% to 33%,MA% of the first group is higher than the second.According the results of cluster analysis,it is found that some characteristics,such as assimilation of trehalose,melezi- rose and maltose etc.,can be used in identification of this genus,but others used in conven- tional identification method can't.The similarity coefficient of C.insectorum and C.terebra is 90%,so they should be merged as one species.